Physical Sciences and Mathematics Commons^™

Effects Of Heavy Metals On Benthic Macroinvertebrates In The Cordillera Blanca, Peru, George L (George Livingston) Burgess

WWU Graduate School Collection

Glacial retreat as a result of global climate change is causing ongoing alterations in the hydrogeochemistry of streams in the glacial foreland of the Cordillera Blanca mountain range in Ancash, Peru. Changes in water chemistry include increased concentrations of toxic metals and decreased pH, which have the potential to affect the structure of benthic macroinvertebrate communities in impacted streams. This study measured physical-chemical water quality parameters, metal concentrations, and macroinvertebrate abundances at 29 sample reaches throughout seven valleys located in Huascaran National Park. The relationships of invertebrate abundances and metrics of community structure to water quality parameters, including metal concentrations, …

Profiling Sortase Substrate Specificity Using Peptide Libraries, Keyvan Dastkhosh Nikghalb

WWU Graduate School Collection

The use of enzymes for protein modification chemistry has gained traction in recent years due to the remarkable site-selectivity that enzymes afford. Among enzymes reported for this purpose, sortase A from Staphylococcus aureus (SrtAStaph) has garnered significant attention because of its selectivity, and its ability to install a wide range of non-natural modifications. In addition to SrtAStaph, it is now appreciated that sortase homologs exist in many bacterial strains, each with the potential to serve as a new catalyst for protein engineering. However, the majority of these enzymes has not been studied biochemically, and in order to utilize these enzymes …

Poly(Vinylpyridine) Nanostructures For Nanoparticle Synthesis And Energy-Related Catalysis, Audrey Taylor

WWU Graduate School Collection

Synthetic methodologies that allow for intentionally designed structures Pt_xM_100-x with a specified size, composition, and inter-particle spacing are key to advancing the field of energy-related catalysis. The synthesis of these catalytic nanostructures can be carried out using well-defined polymer frameworks that selectively retain catalyst precursors. Poly(vinylpyridine), (PVP) a polymer bearing pyridine residues is capable of metal-coordination or electrostatic association with metal anions in acidic media. In this work, we explore the synthesis of cross-linked PVP colloids and block copolymer templates capable of loading with catalyst precursors (ie: PtCl₆^2-, AuCl₄^-, IrCl_{6 …}

High-Mg Andesites From The Northern Cascade Arc: Using Mineral Chemistry To Distinguish Between Hypotheses For Petrogenesis, May Sas

WWU Graduate School Collection

A fundamental question in the Earth Sciences is whether, in certain situations, subducting lithospheric plates can get hot enough to generate melt that consequently contributes to magmatic output in volcanic arcs. Because the subducting plate beneath the Cascade arc is relatively young, and therefore understood to be hotter than older subducting slabs, slab melt generation is considered possible. Recent work has shown that slab melt is involved in magma petrogenesis in the southern Cascade arc (Walowski et al., 2015). To better understand the role of slab melt in north Cascades magmas, this study focused on petrogenesis of high-Mg lavas from …

Probing The Hydrodesulfurization Properties Of Nickel-Rich Bimetallic Phosphides: Supported Catalysts And Encapsulated Nanoparticles, Samuel J. Danforth

WWU Graduate School Collection

The need for improved hydrodesulfurization (HDS) and hydrodenitrogenation (HDN) catalysts is being driven by increasingly demanding requirements for ultralow sulfur fuels and by the fact that sulfur levels in crude oil have been trending upward over recent decades. Current industrial catalysts are based on molybdenum sulfide (MoS₂) and its highly anisotropic structure severely limits the number of exposed active sites. Transition metal phosphides (e.g. Ni₂P/SiO₂) are a new class of materials with promise to have improved properties relative to sulfided Ni-Mo/Al₂O₃ catalysts. The addition of a second metal can have large …

Marine Microzooplankton Are Indirectly Affected By Ocean Acidification Through Direct Effects On Their Phytoplankton Prey, Kasey Kendall

WWU Graduate School Collection

To date few studies have explored indirect effects of OA on microzooplankton. Microzooplankton grazing behavior is acutely sensitive to prey cell size, physiology, and nutritional state, which may all be influenced by OA in phytoplankton. Therefore, microzooplankton may be indirectly affected by OA through their prey. Due to undersaturation of CO₂ for the carboxylating enzyme, RuBisCO, increasing availability of CO₂ through acidification could affect algal cellular processes, physiological states, and the nutritional value for their primary consumers. In this study I tested for indirect effects of OA on three microzooplankton species, representing two ecologically significant functional groups of …

Ocean Acidification Affects Larval Swimming In Ostrea Lurida But Not Crassostrea Gigas, Shannon Buckham

WWU Graduate School Collection

The effects of ocean acidification (OA), which results from increased CO₂ emissions, are of particular concern for calcifying marine organisms. In marine invertebrates, the larval stages are generally considered the most vulnerable to the effects of OA and many recent studies show negative impacts of OA on early developmental stages of calcifying marine invertebrates. I studied the impact of OA on larval swimming performance and behavior in the Pacific oyster, Crassostrea gigas, and the Olympia oyster, Ostrea lurida. Swimming studies can be used to understand how short-term performance and behavior changes may affect the long-term success of …

Incorporating Experiential Education Into Entry-Level College Biology Curriculum, David W. Droppers

WWU Graduate School Collection

Through a literature review and application from personal experiences, this paper acts as a best methods guide for incorporating experiential education in higher education biology/life sciences curricula. The advantages of experiential education are explored, as well as how to best employ them to maximize gains. As experiential education is on the decline, this paper outlines what may be lost from a student’s education experience. This paper explores in particular entry-level college biological/life sciences curricula, as well as the pedagogy of entry-level college students. Throughout the paper, I reflect on how I have applied these methods through field trips as part …

Determining Biologically Available Phosphorus In Storm Water Entering Lake Whatcom, Wa Using The Dual Culture Diffusion Apparatus, Jonnel Deacon

WWU Graduate School Collection

Long term monitoring of Lake Whatcom, a large monomictic lake located near Bellingham, Washington, has indicated a decrease in water quality that resulted in excessive algae growth associated with increased phosphorus inputs. Recently, a total maximum daily load was issued to limit phosphorus inputs into the lake, with emphasis on storm water mitigation. Not all phosphorus in storm water can be used by algae; the portion that can be used is described as bioavailable, and includes both inorganic and organic forms of phosphorus. My research focused on quantifying the amount of phosphorus made available by alkaline phosphatase, an algal and …

Integrated Human Health And Ecological Risk Assessment For The South River, Virginia: A Bayesian Approach, Meagan J. Harris

WWU Graduate School Collection

Regional scale risk assessments can be used to determine the likelihood of effects from multiple stressors on ecological or human endpoints at multiple scales. The Relative Risk Model framework can incorporate ecosystem services as endpoints in this multiple stressor- multiple endpoint approach. Through this research, I aimed to demonstrate an approach to integrating ERA and HHRA that could be applied to assess risk to human health and ecosystem services using the South River, VA as a case study. I applied the Relative Risk Model with Bayesian networks (BN-RRM) to an integrated assessment of four ecosystem services of the South River, …

Structural Requirements For Ribosome-Dependent Gtpase Activity And Binding, Markus A. Carlson

WWU Graduate School Collection

The two billion years of evolution since the divergence of prokaryotes and eukaryotes has left earth with very few molecules conserved across these two domains of life. One such molecule, the ribosome, is an enormous ribonucleoprotein responsible for translation, the process of converting the information contained within an organism’s genetic code into functional proteins. Translation is facilitated by a number of other proteins, termed translation factors, required to catalyze the synthesis of these proteins. A large number of antibiotics prescribed today target either the ribosome or translation factors, and with increasing antibiotic resistance being found in infectious bacteria there is …

Effects Of Hypoxia And Sulfide Intrusion On Eelgrass (Zostera Marina), Melissa Ciesielski

WWU Graduate School Collection

Eelgrass, Zostera marina, provides critical habitat for many marine species in the Pacific Northwest. Although most eelgrass beds in the Salish Sea are stable, a few areas are experiencing decline. One region experiencing eelgrass decline is Hood Canal, a region that also has frequent hypoxic events. Hypoxia has the potential to be a stressor to eelgrass as it can lead to tissue anoxia at night. These tissues then must undergo anaerobic metabolism, which is less energetically efficient and can produce toxic byproducts. Hypoxia may also work in synergy with other stressors, such as sediment pore-water sulfide. Hypoxia can facilitate …

Gold(Iii)-Catalyzed Cyclizations To Form Saturated Oxygen Heterocycles, Ryan D. Lyski

WWU Graduate School Collection

Gold catalysis has emerged over the past decade as an important methodology in the construction of organic molecules. Cationic gold complexes are robust, versatile, selective and efficient catalysts that can be used to enhance the electrophilicity of C-C unsaturated bonds. A current area of investigation is the use of gold to activate allylic alcohol/ether moieties for intramolecular S_N2’ nucleophilic attack to form oxygen heterocycles. We have discovered that sterically bulky, electron-withdrawing oxygen leaving groups drastically improved reaction efficiency, and bulky leaving groups in combination with substrate substituents enhanced diastereomeric ratios in the oxygen heterocycle products. These reactions proceeded …

Effect Of Symbiotic State On The Fatty Acid Composition Of Anthopleura Elegantissima, AndréS J. Quesada

WWU Graduate School Collection

Anthopleura elegantissima, the most abundant intertidal sea anemone on the Pacific coast of North America, naturally occurs in three distinct symbiotic states: zooxanthellate (hosting the dinoflagellate Symbiodinium muscatinei), zoochlorellate (hosting the chlorophyte Elliptochloris marina), and aposymbiotic (lacking symbionts). S. muscatinei is more productive during summer months and may translocate considerably more carbon to the sea anemone host than does E. marina. Quantitative and qualitative differences in the contribution of energy from the symbiont are believed to affect host lipid levels, influencing growth and reproductive output. To study the effect of symbiotic state on host lipids in …

Differential Incision And Uplift Of The Yakima River Terraces, Adrian M. Bender

WWU Graduate School Collection

The Yakima fold belt comprises fault-related folds deforming Miocene basalts and younger deposits of the Columbia Plateau in central Washington State. Geodesy implies ~2 mm/yr of modern, NNE-directed regional shortening; however the distribution of Quaternary deformation among individual structures remains unclear. South of Ellensburg, Washington, the Yakima River cuts a ~600-m deep canyon across several of the folds, preserving flights of strath terraces that record the progressive incision. Graded alluvial basins at the head and mouth of the canyon imply that terrace incision also records differential rock uplift. We integrate lidar analysis, field observations, and cosmogenic burial dating of eight …

Structural Studies Of Blood Coagulation Factor Viii In Protein Complexes, Michelle E. Wuerth

WWU Graduate School Collection

A deficiency in blood coagulation factor VIII (fVIII) is responsible for the inherited bleeding disorder hemophilia A, which affects approximately 1 in 5000 males. The development of inhibitory antibodies is a significant issue faced by hemophilia A patients receiving therapeutic infusions of fVIII. The C-terminal C2 domain of fVIII has been shown to be highly immunogenic and the site of binding for numerous antibodies of both the classical and non-classical classifications. A detailed understanding of the structural components involved in C2-antibody binding interactions is vital for the development of improved therapeutics for hemophilia patients. Here we present the structure of …

The Effect Of American Kestrels On Deterrence Of Bird Damage To Pacific Northwest Sweet Cherries, Deanna K. Leigh

WWU Graduate School Collection

Bird damage to fruit crops causes major economic loss to growers. The Pacific Northwest leads sweet cherry production in North America, but few studies highlight the impacts of bird damage to cherries in this region. Growers currently employ a diverse range of bird-deterrent strategies, but there is little information regarding efficacy. A low-impact management practice common to the region is the use of kestrel nest boxes in orchards. The American kestrel (Falco sparverius), is a small falcon that may mitigate damage because it is territorial and preys on birds. My research objectives were to quantify bird damage and …

An Ecogeomorphic Model To Assess The Response Of Padilla Bay's Eelgrass Habitat To Sea Level Rise, Katrina L. Poppe

WWU Graduate School Collection

Estuaries worldwide are facing the possibility of conversion to open water if accretion cannot keep pace with increasing rates of sea level rise. Recent research into sediment elevation dynamics in Padilla Bay, a National Estuarine Research Reserve in Puget Sound, has revealed a mean bay-wide elevation deficit of -0.37 cm yr-1 since 2002. However, a more mechanistic prediction of the estuary’s response to future sea level rise should also incorporate non-linear feedback mechanisms between water depth, plant growth, and sediment deposition. Therefore, I used measurements of sediment accretion rates, suspended sediment concentrations, eelgrass stem density, and above- and belowground eelgrass …

Paleomagnetic Determination Of Vertical-Axis Block Rotation And Magnetostratigraphy In The Mecca Hills And Coachella Valley, California, Cassidy W. (Cassidy Wade) Dimitroff

WWU Graduate School Collection

Our ongoing work on the paleomagnetism and magnetostratigraphy in the Coachella Valley has provided an improved understanding of the timing and spatial variations of sediment accumulation and deformation during evolution of plate-boundary fault zones. Here, we report updated results from the Palm Spring Formation of the Mecca Hills, and new paleomagnetic data from Pleistocene conglomeratic sandstone in Desert Hot Springs and the Plio-Pleistocene San Timoteo Formation from Live Oak Canyon.

From the Mecca Hills, new data were obtained-112 samples from 29 sites. The majority of the paleomagnetic results yielded well-defined components of magnetization, which allowed us to identify seven well …

Surface Slip During Large Owens Valley Earthquakes, Elizabeth K. Haddon

WWU Graduate School Collection

The 1872 Owens Valley earthquake ranks among the largest historical earthquakes in California. Relatively sparse field data and a complex rupture trace inhibited attempts to define the slip distribution and reconcile the total moment release. We present a new, comprehensive surface-slip record based on lidar and field investigation, documenting 183 measurements of laterally and vertically displaced landforms for 1872 and earlier Owens Valley fault earthquakes. Our lidar analysis uses a newly developed analytical tool to measure fault slip based on cross-correlation of sub-linear topographic features. This MATLAB-based GUI, OffsetXcor, produces a uniquely-shaped probability density function (PDF) of fault slip for …

High-Sr Volcanic Domes From The Lassen Volcanic Region, Southernmost Cascade Arc, Northern California: Implications For Andesite And Dacite Magma Generation, Christina M. Stout

WWU Graduate School Collection

The Onion Butte (OB) and Barkley Mountain (BM) groups are two lineaments of volcanic domes and lava flows located with the Lassen segment of the southernmost Cascades, northern California. The OB group (_~2.5 Ma) consists of 13 domes that are dominantly dacitic, but span the range from andesite to dacite. The BM group (_~1.5 Ma) comprises 21 domes that range from basaltic andesite to andesite, but are mostly andesitic.

The lavas of both groups are petrographically similar, but differ geochemically. The lavas are fine-grained, sparsely phyric containing needle-like hornblende phenocrysts, but lack the large plagioclase phenocrysts …